Project Summary/Abstract Disruption of mitochondrial transport, distribution and dynamics arises early in the progression of multiple neu- rodegenerative disorders caused by environmental and genetic factors, and could be a causative factor in neu- ronal failure. However, the molecular mechanisms of mitochondrial trafficking inhibition and biomarkers of early mitochondrial dysfunction are undefined. Lack of such knowledge limits development of tools for early diagno- sis, monitoring disease progression, and design of efficient therapeutic strategies for neurodegenerative disor- ders. The objective in this application is using advance technologies to develop an integral panel of mitochon- drial/metabolomic biomarkers for early diagnosis of mitochondrial dysfunction in neurodegenerative disorders caused by genetic and environmental factors and to determine molecular mechanism of mitochondrial traffick- ing inhibition that could be common for multiple diseases. The central hypothesis is that genetic and environ- mental stressors initiate mitochondrial dysfunction through the common mechanism that involves disruption of mitochondrial dynamics that reflects on and could be detected early by analyzing dynamic alterations in me- tabolomic signatures and metabolic networks. The rationale for the proposed research is that establishment of mitochondrial and metabolomic signatures as a panel of candidate biomarkers will allow validation in a larger cohort of patients whether these biomarkers could be used for early diagnosis and prediction/monitoring of dis- ease progression. Guided by strong preliminary data, this hypothesis will be tested by pursuing four specific aims: 1) Establish a correlation algorithm between altered parameters of mitochondrial dynamics and signature metabolomic biomarkers in development of mitochondrial dysfunction in neurodegeneration, 2) Validate the use of integral biomarkers of early mitochondrial dysfunction for monitoring the disease progression in trans- genic animal models for AD, HD and PD, and environmental toxicity in vivo, 3) Determine the molecular mechanism of mitochondrial trafficking inhibition induced by environmental and genetic stressors, and 4) Es- tablish the relationship between integral mitochondrial biomarkers and progression of disease in AD, HD and PD patients. We will apply advanced biochemical and cell biology techniques combined with utilization of the analytical metabolomic platforms based on 18O-assisted GC/MS, LC/MS/MS, 1H NMR and 18O-assisted 31P NMR technologies to establish the relationship between altered mitochondrial dynamics and metabolomic pro- files and global changes in energetic and metabolic signaling circuits in neurons, tissue and body fluids from transgenic animal models and human patients that are associated with Mito dysfunction caused by genetic and environmental stressors. Public Health Relevance: Mitochondrial dysfunction has been shown to play a central role in progression of multiple neurodegenerative disorders caused by environmental stress and genetic factors. Lack of the under- standing of the molecular mechanisms underlying mitochondrial dysfunction precludes the development of effi- cient strategies for early diagnosis, prevention and treatment. The proposed study will determine the mecha- nism by which different genetic and environmental stressors cause mitochondrial dysfunction and will identify relevant metabolomic biomarkers. This study will facilitate understanding of the molecular mechanisms under- lying neurodegeneration and promote the development of tools for drug design, diagnosis and disease moni- toring.